The EU Services Directive: http://www.berr.gov.uk/whatwedo/europeandtrade/europe/services-directive/page9583.html  
A presentation of the EU Services Directive published by the UK Department for Trade and Industry. Useful information on trading and marketing of services within the EU internal markets.

World Trade Organization’s Services Gateway: http://www.wto.org/english/tratop_e/serv_e/serv_e.htm
Contains the latest information on the General Agreement on Trade in Services (GATS) at the Uruguay Round of WTO trade negotiations. Research and discussion papers range from architecture to voice-mail telecommunications and to space transport. An essential online resource for the latest news and discussion on global trade in services.

The International Trade Centre: http://www.intracen.org/
The International Trade Centre (ITC) is the technical cooperation agency of the United Nations Conference on Trade and Development (UNCTAD) and the World Trade Organization (WTO) for operational, enterprise-oriented aspects of trade development. ITC supports developing and transition economies, and particularly their business sector, in their efforts to realize their full potential for developing exports and improving import operations. This link provides some very useful information, statistics and resources on international trade in services.

International Chamber of Commerce: http://www.iccwbo.org/
The International Chamber of Commerce’s website provides a range of information and resources on the development of services trade liberalization, and international trade in general.